Photographic emulsions sensitized with alkylene oxide polymers and quaternary ammonium salts



United States Patent ()1 3,017,271 Patented Jan. 16, 1962 ice 14 Claims. (Cl. 96-107) This application relates to photography and particularly to sensitizing photographic emulsions.

This application is a division of my copending US. patent application Serial No. 550,495, filed December 1, 1959, now US. Patent 2,886,437, granted May 12, 1959, for Photographic Emulsions Sensitized with Alkylene Oxide Polymers and Quaternary Ammonium Compounds.

It is well known that silver halide emulsions may be chemically sensitized with a variety of materials in order to increase the speed and generally the gamma of the emulsion, as opposed to optical sensitization in which the optical range of sensitivity is increased. Chemical sensitization usually results either from the formation of silver sulfide on the surface of the silver halide crystal, thus increasing sensitivity, or from the formation of small amounts of silver from the reduction of silver halide. Other classes of compounds, such as certain ethylene oxide condensation products and certain cationic surfaceactive salts increase sensitivity of silver halides Without apparently entering into chemical combination with the silver halide.

Carroll US. patent 2,271,623, Carroll and Allen US.

patent 2,288,226 and Carroll and Spence US. patent 2,334,864 describe the chemical sensitization of silver halide emulsions with quaternary ammonium compounds.

I have now found that the light-sensitivity of silver halide emulsions which have been sensitized with alkylene oxide polymers not containing a quaternary ammonium group, with and Without optical sensitizing dyes, may be further increased by the use of quaternary ammonium compounds, and that this increase in sensitivity is not accompanied by an increase in graininess. The polyalkylene oxide polymers and quaternary ammonium compounds can be used in combination in several ways to produce sensitivity increases, i.e., the compounds may be added to the emulsion, the emulsion may be treated With the compounds before exposure and development, or by the addition of at least one of the compounds to the developer. Thus it is possible to produce the sensitivity increases by using one of the above procedures for both compounds (e.g., adding both to the emulsion before coating) or by using the compounds in different procedures (e.g., adding the polyethylene oxide to the emulsion and the quaternary ammonium salt to the developer), as illustrated by the examples hereinafter.

The quaternary ammonium silver halide sensitizing agents useful in the invention in conjunction with the alkylene oxide polymers include a wide variety of well known quaternary ammonium salts such as disclosed in US. Patents 2,288,226 and 2,271,623.

An important group of these salts are the tetraalkyl quarternary ammonium salts having the general formula in which X is an anion or acid radical, for example, halide, p-toluene sulfonate, alkyl sulfate or perchlorate, R, R R and R are alkyl groups of which at least one'has a chain of seven or more atoms such as carbon atoms, carbon atoms plusoxygen atoms, sulfur atoms or nitrogen atoms and ring systems, While the remaining R groups are alkyl such as methyl, ethyl, butyl, and benzyl as exemplified hereinafter.

Another group of the quaternary ammonium salts, in which the quaternary nitrogen atom is a part of a ring system, has the general formula ,2. --i I-R 1;

where X is as above and R represents a chain of at least seven atoms such as above; however, R may be an aralkyl group as small as fi-phenyl ethyl, and Z represents the atoms necessary to complete a cyclic structure such as a pyridyl, a-picolyl, piperidyl or morpholinyl nucleus. If R contains a second quaternary nitrogen atom, a long chain may link the nitrogen atoms as in the bis-quaternary ammonium compounds tabulated hereinafter.

Examples of the quaternary ammonium salt sensitizers are given in the following table, the compound number for each salt being that utilized in the emulsion examples hereinafter.

Compound No. Quat. I Decamethylene a w bis(oxymethylpyri dinium perchlorate) II Laurylpyridinium perchlorate III Decamethylene bis (oxymethyl-a-picolinium perchlorate) IV p-Xylylene-bis-(pyridinum perchlorate) V Hexamethylene bis(oxymethylpyridinium perchlorate) VI Hexadecylpyridinium bromide VII Decamethylene-bis(oxymethyldimethylbenzylammonium perchlorate) VIII Decamethylene bis(N-methylpiperidinium perchlorate) IX Lauryl pyridinium-p-toleuenesulfonate X N n Tetradecyl-N-methylmorpholiniump-toluene sulfonate XI Lauryl trimethylammonium-p-toluene sulfonate XII n Myristyl-trimethylammonium-p-toluene sulfonate XIII Decamethylene-bis-trimethylammonium bromide XIV Decamethylene-bis-trimethylammonium perchlorate XIVa Tetradecamethylene-bis(pyridinium perchlorate) These quaternary ammonium compounds can be ob tained by the methods described in the above patents.

The quantity of quaternary ammonium compound which is most advantageously employed varies with the nature of the quaternary ammonium compound and with the nature of the emulsion. Ordinarily, the most advantageous concentration has been found to be between about 50 mgs. and 5000 mgs. of the quaternary ammonium compound per gram mole of silver halide in the emulsion, although greater or smaller concentrations can be employed. We have found that excesses of the quaternary ammonium compound are to be avoided since excesses produce fog in the emulsions. The optimum range of concentration for any quaternary ammonium compound described herein is. ordinarily fairly narrow and can best be determined by employing a series of concentrations of the quaternary ammonium compound separately in several batches of the same emulsion and determining the sensitivity of the several batches before and after incorporation of the quaternary ammonium compound, in the usual manner which is, of course, well known to those skilled in the art.

The alkylene oxide polymers used to sensitize the emulsions may be of various types. The alkylene oxides from which the polymers are derived contain from 2 to 4 carbon atoms, e.g., ethylene oxide, propylene oxide and butylene oxide. The preparation of polymers from these compounds is described in Ellis, The Chemistry of Synthetic Resins (1935), pages 990 to 994. These compounds are also referred to as polyalkylene glycols and their use as sensitizers for silver halide emulsions is described in U.S. Patents 2,423,549 and 2,441,389. The alkylene oxide derivates may be prepared by condensing an organic compound containing an active hydrogen atom with an alkylene oxide polymer, or by condensing the active hydrogen compound with the alkylene oxide during the polymerization of the latter material.

Various derivatives of alkylene oxides may also be used to sensitize the emulsions, e.g., condensation products of alkylene oxide with organic compounds containing an active hydrogen atom. Examples of active hydrogen organic compounds, i.e., compounds in which a hydrogen atom may be replaced by reaction of the compound with metallic sodium, methylmagnesium iodide, etc., include alcohols, amines, mercaptans, acids, amides, hydrocarbons such as acetylene, and compounds having the active hydrogen in a methylene group such as dibenzoylmethane. More specifically, we may employ condensation products of alkylene oxide with glycols such as those having from 8 to 18 carbon atoms as described in U.S. Patent 2,240,472 and British Patent 443,559 as well as .condensation products of alkylene oxides with aliphatic alcohols, condensation products of alkylene oxides with aliphatic acids, e.g., lauric acid and glycine, condensation products of alkylene oxides with aliphatic amines or amides, e.g., glycine and lauryl amide, and condensation products of alkylene oxides with phenols, e.g., phenol. The preparation of these condensation products is described in U.S. Patent 1,970,578. Condensation products of alkylene oxides with hexitol ring dehydration products as described in U.S. Patent 2,400,532 may also be employed.

In each case the polyalkylene oxide or derivative of alkylene oxide should have a molecular weight of at least .300. Condensation products of ethylene oxide with long chain alcohols, acids, amines or amides should have a molecular weight ofabout 700. In general, the best results are obtained with the condensation products of ethylene oxide with long chain compounds having a chain length of 12 or more carbon atoms and with ethylene oxide polymers having a molecular weight of 1500 to 4000 or more.

When employing optically sensitized emulsions the optical sensitizing dyes are advantageously employed in about their optimum concentration which ordinarily lies dye per liter of emulsion containing about 0.25 gram mole of silver halide although concentrations above or below the optimum concentration can be employed.

between about 10 mgs. and 40 mgs. of optical sensitizing tographic Process, 1942, page 3).

with the sensitizing with alkylene oxide polymers.

HOCH CH O(CH CH O) CI-I CH OCOC H Polyethylene oxide oleic ester where n =an integer greater than about 10.

Polyethylene oxide nonyl phenol ether N-methyl myristylamino polyethylene oxide N-methyl-n-dodecylamino polyethylene oxide N-methylmyristylaminopolyethylene oxide 1045 can be prepared as follows:

In a flask equipped for gas addition is placed 10 parts of N-methylmyristylamine (prepared by lithium aluminum hydride reduction of N-methylmyristamide) and a catalytic amount of boron fluoride-ethyl other complex. Ethylene oxide is added slowly over a period of 12 to 15 hours until 46 parts of the gas is absorbed. The optimum reaction temperature is to C. The product so obtained is a light amber colored Waxy material; the color may be removed partially by treatment with charcoal in a suitable solvent.

This material is representative of a number of condensation products of ethylene oxide with secondary amines the alkyl chain of which should contain at least nine carbon atoms and the polyethylene oxide chain should have a molecular weight of at least 500.

The preparation of silver halide emulsions involves three separate operations: (1) the emulsification and digestion or ripening of the silver halide, (2) the freeing of the emulsion from aqueous soluble salts usually by washing, (3) the second digestion or after-ripening to obtain increased sensitivity (Mees, The Theory of the Pho- The sensitizing agents may be added at any stage, preferably after the final digestion.

The photographic emulsions which we use are of the developing-out type and best results have been obtained with gelatino-silver bromoiodide emulsions. However, emulsions of varying halide content may be used.

The emulsions may be chemically sensitized by any of the accepted procedures, in addition to or in combination The emulsions may be digested with naturally active gelatin, or sulfur compounds may be added such as those described in Sheppard U.S. Patents 1,574,944 and 1,623,499, and Sheppard and Brigham U.S. Patent 2,410,689.

The emulsions may also be treated with salts of the noble metals such as ruthenium, rhodium, palladium, iridium and platinum, all of which belong to group VIII of the periodic table of elements and have an atomic Weight greater than 100. Representative compounds are ammonium chloropalladate, potassium chloroplatinate and sodium chloropalladite, which are used for sensitizing in amounts below that which produces any substantial fog inhibition, as described in Smith and Trivelli U.S. Patent 2,448,060, and as antifoggants in higher amounts, as described in Trivelli and Smith U.S. Patents 2,566,245 and 2,566,263.

The emulsions may also be chemically sensitized with gold salts as described in Waller and Dodd U.S. Patent 2,399,083 or stabilized with gold salts as described in Damschroder U.S. Patent 2,597,856 and Yutzy and Leermakers U.S. Patent 2,597,915. Suitable compounds are potasssium chloroaurite, potassium aurithiocyanate, potassium chloroaurate, auric trichloride and 2-aurosulfobenzo thiazole methochloride.

The emulsions may also be chemically sensitized with reducing agents such as stannous salts (Carroll U.S. Patent 2,487,850), polyamines such as diethylene triamine (Lowe and Jones U.S. Patent 2,518,698), polyamines such as spermine (Lowe and Allen U.S. Patent 2,521,925), or bis-(,S-aminoethyl) sulfide and its watersoluble salts (Lowe and Jones U.S. Patent 2,521,926).

The emulsions may also be stabilized with the mercury compounds of Allen, Byers and Murray U. S. application Serial No. 319,611, Carroll and Murray U.S. application Serial No. 319,612 and Leubner and Murray,U.S. application Serial No. 319, 613, all filed November 8, 1952, now US. Patents 2,728,663, 2,728,664 and 2,728,665 respectively, granted December 27, 1955.

Other stabilizing agents may he added to the emulsions containing the quaternary ammonium compounds and polyalkylene oxides such as cadmium chloride, cadmium nitrate, cobalt nitrate, manganese chloride, man-. ganese sulfate, zinc chloride, zinc nitrate and zinc sulfate.

When using the combination of the quaternary ammonium compound and the ethylene oxide polymer for sensitizing photographic emulsions the fog was found to be increased somewhat on both fresh and incubated samples of the developed emulsion. This fog was reduced to normal levels by use of an antifoggant such as an azaindene, for example, a 4-hydroxy-6-alkyl-1,3,3a,7-tetraazaindene specifically 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene and 5-carboxy-4-hydroxy-1,3,3a,7-tetraazaindene.

These and other azaindene compounds useful for this purpose are disclosed in US. Patent 2,716,062, and

Allen et al. US. application Serial No. 365,541, filed July 1, 1953, now US. Patent 2,735,769 granted February 21, 1956.

Allen et al. US. application Serial No. 426,547, filed April 29, 1954, now US. Patent 2,743,181 granted April 24, 1956.

Tinker et al. U.S. application Serial No. 515,785, filed June 15, 1955, now US. Patent 2,835,581, granted May 5, 1958.

Reynolds US. application Serial No. 520,120, filed July 5, 1955, now US. Patent 2,756,147, granted July 24, 1956.

Carroll et al. US. application Serial No. 426,543, filed April 29, 1954, now US. Patent 2,743,180 granted April 24, 1956.

Zeitschrift fiir Wiss. Phot. 47, 2-28 (1952).

However, the speed increases are nevertheless obtained using the quaternary compounds in the absence of such antifoggants as attested by the examples hereinafter.

The following examples illustrate my invention.

In the examples the polyalkylene oxides and derivatives thereof are identified as follows, the number following each name indicating the molecular weight of the particular polyethylene oxide chain.

Compound No.

PEO XV Oleyl ether polyethylene oxide 1800 PEO XVI Oleic ester polyethylene oxide 1000 PEO XVII Oleic ester polyethylene oxide 6000 PEO XVIII Nonylphenol ether polyethylene oxide 1145 PEO XIX N-Methylmyristylamino polyethylene oxide PEO XX Oleyl ether polyethylene oxide 1500 PEO XXI N-Methyl-n-dodecylamino polyethylene oxide 1145 PEO XXII Polyethylene oxide 1540 PEO XXIII Polyethylene oxide 4000 The particular tetraazaindene used in the examples, 4- hydroxy-6-methyl-l,3,3a,7-tetraazaindene, is identified as Ala.

EXAMPLE 1 Addition of the polyethylene oxide, quaternary ammonium salt and azainldene to the emulsion before coating To samples of a panchromatic gelatin-silver bromoiodide emulsion which has been digested with a sulfur compound such as disclosed in Sheppard US. Patent 1,574,944 and potassium chloroaurate were added the compounds shown in the following table. The emulsions were coated on a cellulose acetate support in the conventional manner. The coatings were exposedon an Eastman type I-b sensitometer and processed for 5 minutes in Kodak Developer DK-50 having the following composition With the results shown in the following table, speed being read as 30/E where E is the exposure in meter candle seconds required to produce a density of 0.2 over fog:

Developer DK-SO: Grams N-methyl-p-aminophenol sulfate 2.5 Hydroquinone 2.5 Sodium sulfite, desiccated 30.0 Sodium metaborate 10.0 Potassium bromide 0.5 Water to make 1 liter.

Grams Compound per mole 30/E Gamma Fog AgX 0 5,700 .91 .03 1.5 7,050 .87 .04 g g 9,000 .97 .04 kg 12,200 .90 .09 1.5 Y 5.0 13,400 1.07 .10 2.5

This example readily shows the supersensitizingeifect of the combination of the polyethylene oxide with the quaternary ammonium compound. Sample 801 containing the oxide has a speed of only 9900, and sample 792 containing the pyridinium compound has a speed of only 12,200, whereas the combination of the two in the emulsion as in sample 804 yields a speed of 13,400.

EXAMPLE 2 Addition of the polyethylene oxide and tetraazainaene to the emulsion and the quaternary ammonium salt to the developer Coatings were prepared as described in Example 1, except the emulsion contained the following addenda and was processed in the following developers for the indicated times:

v 5 DK-50 5 DK50+0.5 g./l. Quat Grams XIII Sample Compound per mole 30/E Gamma Fog 301E Gamma Fog 7 EXAMPLE 3 Addition of quaternary ammonium salt and tetraazaindene to the emulsion and the polyethylene oxide to the developer 8 EXAMPLE 5 Addition of one or all of the polyethylene oxide, the quaternary ammonium salt, and the azaindene, either to the emulsion or to the developer The coatings were prepared as described in Example 1, except that the emulsion contained the addenda de scribed in the following table. The coatings were exposed 3' DK-50 3' DK50+2.0 g./l. PEO Grams XV Sample Compound perrnole AgX 30/E Gamma Fog 30/E Gamma Fog on a 'I-b sensitometer and processed in the developers given, for the indicated times.

5' DK-50+ 5' DK-50+ 5' DK-50+2 Grams 5'DK-50 2g./1. PEO IgJL'Quat g./l.PEO

per XV I XV-i-l g./l. Sample Compound mole I Quatl 30/E Fog 30/E Fog 30/E Fog 30/E Fog 007 7,700 .25 10,900 .28 15,800 .42 19,000 5.43 908 Aza 1.7 8,850 .25 12,200 .20 10,900 .47 22,000 .48 900--.--{i1fi .H 15,000 .31 15,000 .33 19,500 .55 21,500 1.53 910-.- {8 1 }15,000 .37 10,500 .30 10,500 .53 22,500 ..53

Aza 1.7 011 PEO XV- 1.0 }20,000 .45 10,000 .40 17,700 .01 23,000 .00

Quat I 2.5

EXAMPLE 4 Addition of the polyethylene oxide, quaternary ammonium salt and stabilizing agents to the emulsion before coating cated in the table are measured as 100 (l-log E), where E is the exposure in meter candle seconds required to produce a density of 0.3 above fog.

The data can be quickly assessed by noting that the speed values (of Samples 907, 908 and 909) 7700, 10,900, 8850, 12,200, and 15,000 represent development with the quaternary compound present in neither emulsion nor 'developer.

The example clearly illustrates that the quaternary ammonium compounds are highly efiective when present in the developer alone or together with the'polyethylene oxides, for the development of emulsions free offer containing either or {both of these sensitizing agents. 7

Grams 5 DK-50 12 DK-50 Sample Compound per Mole AgX Speed Gamma Fog Speed Gamma Fog 20. 0 1. 5 Aza. 2.0 679 Quat. XIVa--. 0.5 386 67 09 407 98 20 CdCl2; 20.0 EDGS 1 20. 0

filed September 6, 1955.

, either within one day after k at 120 F.,

10 EXAMPLE 9 ere added. The coatings were exposed in Example 1 or after a period of one wee been added polyethylene oxides and quaternary salts To an emulsion similar to that described in Example 1,

Use of azaindenes to stabilize emulsions to which have 5 the following w and processed as coating (fresh), 55 percent relative humidity.

75 processed as in Example 1. The example further illus- EXAMPLE 6 ammonium salt, or the azaindene either directly to liquid emulsion, or by means of a pre-exposure bath of the coated film The coatings were prepared as described in Example 1, except that the emulsion contained the addenda described below. The coatings, after being bathed for 5 minutes Addition of one of the polyethylene oxide, the quaternary m lw mmm m m w w u w w M w M M wmm U m m 1 2 63 E G ma m n m mwm m6 mmuim a S a 168 6 3 2 7 11144194 Ec m lol e1zmmaamaaammummawa Ew 2. 2 2 2 9W2 2 2 m% m 111 1 1 1 1 1 l 1 L1 1. 1 1 1. L1 HS 0 a .la F wew G dW m Wn M e. m mmmm wmmm m m m m m mww m o w m mooom m Wu F mm w W m wmv oo 5 4 m 6 0 9 4 99 7 m 8 9 MW%% 2 7 4 8 1 I t 1 w m mm, mmem m mwammmma mumm mm m 3 1 1 1 $6 1 e E m e H 1V1, 1111111111 111 111 1 i t e it 11 1 l L hm m .enennennhhsnhhheannme n nn n "093550 E me mWX QW7 W M T V momma ..222212122121221212Q11QQLLQL2QQLZQLLLLLQ woonmmqwmmoo 8 g .1 0 100 11 0 GW t Gm. m n E.1.m S ununflnuu "nun" "n" fl a n 3 1; mwmw m Liinfi i i mm n 5 I. m m m m n o vuv" wv m lm mm m D. 6 II 0 X1 X1 m .m E W m n "X LX X V H 0 m n a n n m o m a a a n u no "a .mf C M nW mw Ennuw Eu .m H O 0 ZEZEUZEZE Z uEwmE mu be A P P0 mtmrm N Q APQAPAP A QPAAP AQ mm fid u d ed M mm n a w m m n u m m m m m m m mm m m m n p p m I a m u a a n n a n n 0 I u u m a cc s mam mm m aaaeaaeaaa 5 m e 0 0 .1 8 8 9 9 9 1 3 33 3 6 3 3 3 3 3 w w M M M4. M N M W 0 0 0 5 0 5 0 5 1 2 3 3 4 4 5 5 w 164 8 5 7 34 3 6 4 m W M W. G M We WM W W m M H W ID o CS .8 a 8% g v ak M mm. m n R r p e e mmmmm mm m me 0 0 1, 1 i e h 9 C v mK 3 name m mm m amen Wm mm a an: m m m m m m m mm amam mmmw m 311 u m jmmmmmmm m s I n 1 a ds 0 m as o I u U a u u n em m u 610 62. f mg u u u u n u ,m g u u N M "mm mm m m w n o o oo o o o o o o 0 am He Tn." Z; w than, mn E mmmmemaawmm n .ir LUI. 7 5 a w 00 0 W 9 27 00 22 5 9 1 L d m w 8 c 00 c 3 1 1 1 1 1 1 5 0 IOM & M 6 nm 1). eul 6 COP W mu m U M m 6 e e e E n U M 3 1.11 1. 1111 r a l D e HQ wu Q n P m L m mX 7 H W m L mMX N7NW777fifi7fifi757m7fi75fi75fi75fi d t t 0 e a 10101010 M h 0 a g QLQQLLLQZLQQLZLQL L2 01:2 nra2d :6 e t .1 A 8 1 w w 111111112 p m m GMLA md GMA E P 0 .mdm e m t E p, a? d i .m a a 2 M Z se m m na m mm n W. 5n mm mw m e m m B3 on n 0 S a O #Um .1 a 0 O 5 D b0 1 C l k n m mm a fm mm dm u n w a U 0 S e m o A m eww 0o mmm s na 06 m e u h u e n C e 0 M10 1 n 6 0 1 P Om 310 1 p D. .f. 0 or D. hm m l ofp m .a p m n a s n T d a d e m u e S 0 d e S Ted 5 9 4 L5. 7 .m ma A .m h 0 1 44 4. a A 1m m m em a a trates the use of various quaternary ammonium compounds in the emulsions.

Sample Compound pgggio le 30/E Gamma Fog 7821 None 6,000 1.06 .15 7822- A m 3. 6, 250 1.10 .15 1823 43325055.: 31% 7824 3:9 10,200 .94 .16

10,400 .98 .18 3.32 7,550 .85 .15 1 2 12,800 1.02 .26 9,500 .93 .20 11,400 .93 .25 3.0 312133 i193 Iii g g 7,550 .05 .12 3:9 8,850 .93 .14 3:35 10,900 1.11 .16 i1? 5,450 1.05 .23 922 {%%53i5in1:: 5:35 i 393 923 ff.l1'xiiji3 i120} 7,700 16 924 {E XXIII" 1 12 0,500 .84 .30

QuatXII.. 0.3

EXAMPLE 12 To a panchromatic emulsion similar to that described in Example 1 were added the following ingredients. The

coatings were exposed and processed as in Example 1.

' Grams 30/E Sample Compound per Mole Speed Gamma. Fog

. AgX

.5 0.75 10,000 .85 .16 0. 75 3,200 1.20 .20 0. 75 5,700 .97 .21 0.75 7,200 .95 .25 PEO XIX 2.25 6, 700 1.13 .32

The emulsions of Example 12 can, of course, contain the indicated quaternary ammonium compounds tofurther increase the light-sensitivity or additionally the other sensitizing agents referred to above prior to the examples. High contrast emulsions conventionally used in the graphic arts for half-tone work and sensitized as in Example 12 with compound XIX exhibit unusually good image quality.

The chemical sensitizing agents and other addenda which I have described may be used in various kinds of photographic emulsions. In addition to being useful in non-optically sensitized emulsions they may also be used in orthochromatic, panchromatic and X-ray emulsions. They may be added to the emulsion before or after any sensitizing dyes which are used. Various silver salts may'be used as the sensitive salt such as silver bromide, silver iodide, silver chloride or mixed silver halides such as silver chlorobromide or silver bromoiodide. The agents may be used in emulsions intended for color photography, for example, emulsions containing color-forming couplers or emulsions to be developed by solutions containing couplers.

The dispersing agent for the silver halide may be gelatin or other colloidal material such as collodion, albumin, cellulose derivatives or synthetic resins.

It will be understood that I contemplate as included within my' invention all modifications and equivalents falling within the scope of the appended claims.

What I claim is:

l. A light-sensitive silver halide emulsion sensitized with a mixture of an alkylene oxide polymer selected from the class consisting of (1) polyalkylene ether glycols and (2) condensation products of an alkylene oxide with organic compounds containing an active hydrogen atom, said alkylene oxide containing from 2 to 4 carbon atoms and said alkylene oxide polymer having a molecular weight of at least 300, and a mono quaternary ammonium salt silver halide chemical sensitizing agent having a chain of at least seven atoms attached to a single quaternary ammonium group.

2. A light-sensitive silver halide emulsion sensitized with a mixture of an alkylene oxide polymer selected from the class consisting of 1) polyalkylene ether glycols and (2) condensation products of an alkylene oxide with organic compounds containing an active hydrogen atom, said alkylene oxide containing from 2 to 4 carbon atoms and said alkylene oxide polymer having a molecular weight of at least 300, and a mono quaternary ammonium salt silver halide chemical sensitizing agent having an alkyl chain of at least seven atoms attached to a single quaternary ammonium group.

3. A light-sensitive silver halide emulsion sensitized witha mixture of an alkylene oxide polymer selected from the class consisting of (1) polyalkylene ether glycols and (2) condensation products of an alkylene oxide with organic compounds containing an active hydrogen atom, said alkylene oxide containing from 2 to 4 carbon atoms and said alkylene oxide polymer having a molecular weight of at least 300, and a mono quaternary ammonium salt silver halide chemical sensitizing agent having a chain of at least seven atoms attached to a single quaternary ammonium group, the emulsion further containing an azaindene as a fog-inhibiting agent.

4. A light-sensitive silver halide emulsion sensitized with a mixture of an alkylene oxide polymer selected from the class consisting of (1) polyalkylene ether glycols and (2) condensation products of an alkylene oxide with organic compounds containing an active hydrogen atom, said alkylene oxide containing from 2 to 4 carbon atoms and said alkylene oxide polymer having a molecular weight of at least 300, and a mono quaternary ammonium salt silver halide chemical sensitizing agent having an alkyl chain of at least seven atoms attached to a single quaternary ammonium group, the emulsion further containing an azaindene as a fog-inhibiting agent.

5. The emulsion of claim 1 wherein the quaternary ammonium salt is a tetraalkyl quaternary ammonium salt.

6. Theemulsion of claim 1 wherein the quaternary ammonium salt is one having a quaternary nitrogen atom which is a part of a ring system.

7. The emulsion of claiml wherein the alkylene oxide polymer is an'ethylene oxide polymer.

' 8. The emulsion of claim 1 wherein the alkylene oxide polymer is a polyethylene oxide oleyl ether.

9. A light-sensitive silver halide emulsion sensitized with a mixture of an ethylene oxide polymer having a molecular weight of at least 300, and a member of the class consisting of laurylpyridinium perchlorate, laurylpyridinium-p-toluene sulfonate, hexadecylpyridinium bromide, N n tetradecyl-N-methylmorpholinium-p-toluene sulfonate, lauryl trimethylammonium-p-toluene sultonate, and n-myristyl trimethylammonium-p-toluene sulfonate.

10. The emulsion of claim 9 further containing an azaindene as a stabilizing agent.

' 11. The emulsion of claim 2 wherein the alkylene oxide polymer is an ethylene oxide polymer.

12. The emulsion of claim 3 wherein the alkylene oxide polymer is an ethylene oxide polymer.

13. A light-sensitive silver halide emulsion sensitized with a mixture of an ethylene oxide polymer having a molecular weight of at least 300 and a monoquaternary ammonium salt silver halide chemical sensitizing agent having a chain of at least seven atoms attached to a single quaternary ammonium group, and containing a stabilizing agent of the class consisting of aminotriazaindenes, aminotetrazaindenes, aminopentazaindenes, hydroxytriazaindenes, hydroxytetrazaindenes, and hydroxypentazaindenes.

14. A light-sensitive silver halide emulsion sensitized with a mixture of an alkylene oxide polymer of the class consisting of (l) a polyalkylene ether glycol and (2) a condensation product of an alkylene oxide with an organic compound containing at least one active hydrogen atom in 14 a radical of the class consisting of hydroxy, amino, mercapto, carboxyl, amido and methylene, said alkylene oxide polymer having a molecular weight of at least 300, and a monoquaternary ammonium salt silver halide chemical sensitizing agent having a chain of at least seven atoms attached to a single quaternary ammonium group.

References Cited in the file of this patent UNITED STATES PATENTS 2,280,722 Schneider Apr. 21, 1942 2,410,690 Smith et al. Nov. 5, 1946 2,694,716 Allen et al. Nov. 16, 1954 2,716,062 Carroll et al. Aug. 23, 1955 2,728,663 Allen et al. Dec. 27, 1955 2,728,666 Carroll Dec. 27, 1955 2,728,667 Knott et al. Dec. 27, 1955 2,784,090 Carroll Mar. 5, 1957 

1. A LIGHT-SENSITIVE SILVER HALIDE EMULSION SENSITIZED WITH A MIXTURE OF AN ALKYLENE OXIDE POLYMER SELECTED FROM THE CLASS CONSISTING OF (1) POLYALKYLENE ETHER GLYCOLS AND (2) CONDENSATION PRODUCTS OF AN ALKYLENE OXIDE WITH ORGANIC COMPOUNDS CONTAINING AN ACTIVE HYDROGEN ATOM, SAID ALKYLENE OXIDE CONTAINING FROM 2 TO 4 CARBON ATOMS AND SAID ALKYLENE OXIDE POLYMER HAVING A MOLECULAR WEIGHT OF AT LEAST 300, AND A MONO QUATERNARY AMMONIUM SALT SILVER HALIDE CHEMICAL SENSITIZING AGENT HAVING A CHAIN OF AT LEAST SEVEN ATOMS ATTACHED TO A SINGLE QUATERNARY AMMONIUM GROUP. 